Knot-tying mechanism



July 9, 1929. D, @RAVEL 1,719,883

xNoT TYING uEcHANIsM Filed uarcn 12, 1925 z sheets-sheet 1 @Hill July 9,1929 D. GRAVEL 1.719.883

KNOT TYING MECHANISM Filed March 12, l1923 2 Sheets-Sheet 2 iwf@ Illll lImill El Izzi/enfer.'

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Patented July 9, 1929.

VP'TENT oFFicE.

DAVIDGIAVEL, OF CHATTANOOGA, TENNESSEE, ASSIGOR TO BARBER-COLMAN COMI- iPANY, 0F ROCKFORD, ILLINOIS, A CORPORATION OF ILLINOIS.

KNOT-TYING MECHANISM.

.Applicationv led March 12,v 1923. Serial No. 624,403.

The invention relates to knot-tying mecha 4nis-ms such as 4ure commonlyemployed iu textile mills for the purpose of uniting threads; and it'hasparticular reference to a device of this character which is capable oitying a small flat knot such as is ordinarily termed in the art aweavers knot.

Numerous eli'ortshave been made in the past to produce a racticalknetter for tying the true weavers rnot, or a variant thereof,

' but Isuch devices have met with limited com- -mercial successfor-various reasons, chief among Awhich is the fact that it has beenhard to hold the parts of the knot from improper shifting movementduring the operation of the knofter, this trouble being perhaps due tothe vdiliieulty in maintaining the correct degree of tension on thevarious strands. y Y

It is the object of my invention to produce an implementato the weaversknotter type which shall be of a thoroughly -practical character'byreason of the reliability with which it holds and operates upon thethreads.

.'Animportant object of the invention is to produce .anl implement ofthis character which `is comparatively simple in construction.. Y Y

In vthe accompanying drawings, Figure 1 is a side elevatlon of myimproved knotter, illustrating-the manner in which the device is mountedVupon thehand ofthe operator. Fig. 2 isa fragmentary elevational viewtaken from the opposite side of the knotter.

Fig. 3 is a fragmentary plan view. Figs. 4 and 5 are fragmentary viewsillustrating details of construction. Figs-6, 7 and 8 are views similarto Fig. 3 but showing the parts in different relativepositions. Fig.'9is a detail hview somewhat diagrammatic in character and.illustratingthe knot just as it is about to be completed. Fig. 10 is a det-vail viewof the completed knot but before it is drawn taut. g

It will be observed that I have illustrated only one embodiment of'theinvention. It is contemplated, however, that various changes inform,construction and arrangement of parts may be made by thoseskilled in theart `without departing from the spirit and scope of the invention asexpressed 1n the appended claims.

,I have herein shown a hand knotter of the general type disclosed inPatent No. 75 3,110

dated March 22, 1904. The present knetter comprises a tying bill to formthe loops-of the knot and to shear one of the threads; means fortightening the loops of the knot and stripping the knot from thetyingbill; means for holding and guiding the threads 1n proper positionfor the knot-tying operation; and a shear for .severing the otherthread. The two threads to be united are herein referred to asa bobbinthread and a spool thread, but these terms are not to be understood aslimitations of the invent-ion. The thread marked bobbin thread on thedrawingmight be the spoolthread, and the spool thread might be thebobbn'thread.

It may be here remarked that for the sake of clearness the-diameter ofthe threads has Vbeen exaggerated in tle views.

Referring now to the drawings, the implement embodies a handle A `and astrap A' together forming a loop whereby thek device may be supportedupon the hand of the operative. -A standard A is rigidly 'fixed to thehandle A and is provided with bearings .for the shaft C3 (Fig. 8) of thetying bill C5. Said tying bill is provided with a pivoted shearing andclamping jaw C14 arranged to be moved to open and close the tying billby means of a cam barrel C. The

tying bill and its shearingr and clamping jaw from the tying billcomprises a thread-hold ing arm E pivoted to swing on the axis D. Theforward end of said arm is in the form of a hook E2 to receive one ofthe threads to be tied, for example, the thread extending from thebobbin. A coiledspring'E3 (Fig. 1) tends to hold the arm Ein its initialposition, such position being determined by contact of the arm with astationary stop A (Fig. 3).

' the loops of the knot and stripping the knot A thread-clamping arm D",provided at its forward end with two upwardly-extending clampinglfingers 1)",1zthat lie at opposite sides offatlie holding 4arm E,pivotedr'at its rear end to one arm of zi b'cll crank D* ot the'bellvcrank'is provided with'a 4rollerstud that liesv in a cam-groove ll (Fig.8) formed in an arcuate iange B which is-Iixed with relation to the gearsegment B7.A The shape of the cam groove-B is such as to cause the bellcrank D" 'to swing hack and forth in cachstroke of the thumb fork B5.During the operating (i. e. downward) stroke of the thumb fork, the armD is advanced so as to cause the fingers l)7 to clamp the thread lyingin the hook E2 of the arm E. As the arm D advances, a spring latch E*(Fig. 6) on the arm E engages a stud D on the bell. crank D, so thatwhen the molement ofy the 'bell crank is reversed the arm E is caused tomove with the bell crank and the arm D (as in Fig. 6), in which movementthe said arms swing laterf ally away from the tying bill to tighten theloops of the knot and strip the knot oit' the. tying bill.A As the thumbfork completes its operativestrokd the spring latch E4 is disengagedfrom thepin D by means of a trigger pin E carried by theflatchrandadapted to engage with a stop pin A on the standard A (Fig. 8). Y Atthe" side ofthe ytying bill, opposite 4to the arms E and DG, is astationary thread guide. C19 for the thread'extending from the s iool. v

1All of the parts thus far described are substantially identical withthe parts bearing corresponding reference. characters in thel)efore-mentioned patent, with the exception of the hook E. which isspeeiall y constructed and arranged in a manner which will presentlyappear. r1 v Cooperating with the thread guide C for supporting thethread extending,r from the spool, is-a guide formed at the forward endof the arm D by'means of an ups-tending `linger 11 (Fig. 2) spa'ccdashort distance inwardly from the fingers D. It will be observed that inthe movement. of the. arm D", said thread guide is carried forwardly,the finger 11 .near the end of such forward movement coacting with anupstanding tinger 12 located near the forward end of the arm E andspacedinwardly from the hook `2. The lingers D"coacting with theopposite sides of the hook E2 constitute a clamp for the bobbin threadlying within the hook; but the finger 11 not being doubled, as in thecase of the fingers D?, reacts with the Enger 12 to position the spoolthread, but. without clamping it therebetween. Accordingly, the spoolthread is permitted to move relative to the guide 11 in the tyingoperation. The primary function, therefore, Aof the guide is t-o holdthe spool-thread in propbill. through the hook E2 isV passed or loopedhe- Yhand the tying billI (see Fig. 3), and then er relation to thetying bill for theinitial yloop-forxnin r operation,iand .-then to move`'the fspool'f t lread forwardly?- adjacent Vthe V yguide hook E for thestripping operation that. swings en thc axis D. 4The other'arm butwithout placing any tension on,` the thread. ,'.lhereasonor 'avoidingtension on this thready isthatit results in the produc- "tion-of a slipknot.

'lhe means for supporting the hohhin thread -xn'ayfcomprise a bracket 13(Fig. G) rigid with the standard A and profs-.ting forwardly and thenlaterally into an inclined position directly in front of the t ying The`bobbin thread after passing Vis brought forwardly to the bracket 13where 1t 1s placed ln a-combined guide and shear 'device designatedgenerally by the numeral 14. This device comprises a stationary platev15l (Figs-1 and 4) -havmg an upstanding `lmger or shear blade. 16. 'Amovable shear blade 17 is rigid with an arm 18 pivoted at 19" andprovided with an inwardly pro- Ajectng vfinger-i2() at.` lts-lower end.

Said linger is' arranged-to be engaged by 'the hi- 'furcatedend 21 'of'alever 22 ivoted upon a'-post`23earried byfthe `brac cet 13. The oppositefor in'nerend of said. lever is beni. downwardly for engagement with thearm '24 ot'the'segment B1 andalso with a hooked member 25l carriedb "thethumb fork Bf'. It. will thus' seenft at' the shear blade 17 is arrangedto be reciprocated in the rockin'r movements ofthe gear segment, thearrangvv 1 ment heing'fsuch that lnear the end of th\`downward'movementof the thumb fork li', the shear 14 seversthe threadheld thereby: and in the return movement of the thumb fork the clampis'opened to receive a new thread.

`Assmning now that-it is desired tounite two threads, for example, abobbin thread and a spool thread,'they are placed in the knettersubstantially in the relation shown in Fig.`3. One 'manner ofaccomplishing this resultis to lay the ends of the two threads parallelacross the palm of the hand with the lingers toward the body and withthe bobbin thread nearest thev ends of the lingers. The threads'arethenplaced in the guides E2 and 11, as shown-in Fig. 6. Now by inverting thcp'alm, the bobbin thread may readily be passed behind the bill Cs andthe spool thread in front of it. vThe free ends` of -the threads arethen manipulated so that the end of thebobbin thread is placed intheshear 14 and the cnd'of the spool thread'lies in the thread guide C.Thus, the threads are crossed `and recrosscd upon o posite 'sides of thetying bill tlriat the formation of a pair of over ping loops a and b isinitially effected. T e thumb fork Bs is now depressed, thereby r0-tating the tying bill in a counterclockwise lll (Fig. Bso

direction. By reason of the relative location of the ortions ofthethreads leading to thel bobliin and the"'spool respectively, as shown-inFigs. Sand 6the'tying bill as it rotates through the first'quarterof itsrevolution engages'saidthreads at a oint between them just'A ahead oftheir initial crossto a point forwardly of t ing. Inthecontinui'edrotation of the bill through a half revolution, the tyingbill twists the loop a (Figs. 6' 'and 7) and as the bill approaches andtravels through the final quarter of its first complete revolution, itengages with the free end of the spool thread, cuts it oil' and' clampsthe same in a well known manner, the end of the spool thread, in suchmovement of the bill, travel- ,ing with it. In the next quarter of arevolution of the tying bill, the arm Ds is moved outwardly, carryingthe arm E with it. Consequently the loops a and b are stripped from thetying bill while the free end of the spool thread held by the billcla-mp is drawn first around the crossed strands of the loop a and thenthrough it, as clearly shown in Fig. 9. The end of the bobbin threadremains loose in the vshear device 14.- while the loops are thus beingstripped from the tying bill (Fig. 8) and in the final outward movementof the arms E and D6 the free end of the bobbin thread is severed by theshear device. After the threads have thus been stri pcd from the bill,and the end of the bobbin thread drawn through the loop a, the billcontinues to rotate through a quarter of a revolution in which the knotis drawn taut (Fig. 5) and the end of the thread held by the bill clampfinally released therefrom.

It will be observed that the thread guide 11 during the strippingoperation (Fig. 8) occupies a position adjacent the hook E. Theconstruction is such, however, that the guide allows the spool thread toslide freely therein in order not to place any tension thereon. Thus theknot is drawn taut solely by the tension laced by the tying bill uponthe free end o the spool thread on the one hand and upon the portion ofthe bobbin thread leading to the bobbin, on the other hand.

In the reverse movement of the thumb fork, the parts are restored totheir initial positions as shown in Fig. 3. I claim as my invention:

1. A weavers knetter comprising, in combination, a frame, a rotary tyingbill mounted in said frame, an arm mounted on said frame and extendingalon side the tying bill ie frame, the forward end of said arm beingbent laterally in front of said tying bill, a member pivoted on saidbent portion of the arm, a second member fixed to the arm with which thelirst member is adapted to coact to shear and clamp the thread, meansfor actuating the pivoted member, and other thread supporting meansadapted to coact with said members to position and tension the threadsin the o )eration thereon by said tying bill'.

2. weavers knetter comprising, in combination,'a frame and means mountedon said frame for tying a weavers knot including thread holding meansand a rotary tying bill adapted to Aoperate upon a pair of threadssupported by said holding means, said thread holding means including anarm carried by the frame and extending alongside the tying bill to apoint in front of the tying bill, said arm being bent forwardly of thetying bill and having a pair of members thereon, one of which is mountedfor pivotal movement relative to the other member, and means foroperating the pivoted member.

3. A mechanism for tying weavers knots having, in combination .with la`tying bill, a thread clamping and stripping device mounted to swinglaterally substantially in a plane containing the axis of the tying billso as to be movable bodily toward and from the tying bill, the free endof said device having means for gripping the-threads so as to tightenthe knot in the movement of the device away from the tying bill, and theend of the tying bill being disposed substantially in said plane duringthe stripping operation.

4. A mechanism for tying weavers knots having, in combination with atying bill, a thread clamping and stripping device mounted to swingsubstantially in a plane containing the axis of the tying bill so as tobe movable bodily toward and from the tying bill, the free end of saiddevice having means for gripping one of the threads lightly and theother tightly and also for moving the lightly held thread relative tothe other whereby to relieve the same of tension in the movement of thedevice away from the bill in the knot-tightening operation.

5. In a tying mechanism for weavers knots, the combination of a tyingbill having thread cutting and clamping means and adapted to operateupon two strands crossed on opposite sides of the tying bill, means forholding the strands on each side of the tying bill spaced a substantialdistance a art, mechanism for operating the tying bil in relation tosaid strands to produce interengaging loop formations therein to formthe knot, and means for tightenin the knot and stripping it from thetying bill including the clamping means of the tying bill adapted toholdone of said strands as the knot is being stripped from the bill, anda device opera le to move one of said strands into closely spacedrelation to Vthe other to relieve tension thereon while placing tensionupon the other one of said strands in the stripping of the knot from thetying bill.

6. In a tying mechanism for weavers knots, the combination of a tyingbill having thread cutting and clamping means and 4 i t 1,71e,a83

adapt ed to operate upon two stra-nds crossed on opposite sides of thetyingrv bi1l,fmechav uisin for operating the' tying bill in relation tosaid strands to produce interengaging .loop formations therein to formthe knot, means for holding the strands a substantial distauceapartduring the knot-forming operation including a device for gripping .bothstrands on one side of the tying hilf, said device being subsequentlyoperable after the formation oi the knot tol move one of said strandstoward the other to relieve it of `tension, andmeans for actuating saiddevice to place tension on said other strand to tighten the knot.

'i'. A Weavers knetter comprising, in combination, a frame, a rotarytying bill mount'- Cd in said'fra-me and having thread cutting andclampingmeans, and means for posi.-

tioniug tvvolgstrandp: relativeito the tying bill so that the tyingbetween the strands and thestrands are erossedon opposite sides ot thetying b1l1," sa`1d positioning means in- DAVID omvat.

have hereunto

